volume | PIER Journals

Abstract

The Medium-Earth-Orbit SAR（MEOSAR）is one of the potential next-generation spacebarne SAR for its excellent performance, however, due to ionospheric effects, a MEOSAR may not be able to produce data useful for science applications. So study of ionospheric effects is one of the critical techniques for the development of MEOSAR. In this paper, we present ionospheric effects on azimuth imaging for MEOSAR. First, we establish an analysis model for ionospheric effects on azimuth imaging of MEOSAR based on the system characteristics of MEOSAR and the temporal-variability of ionosphere. Then, based on the analysis model, we analyze the effects caused by the quadratic and cubic phase errors induced by temporal-variability of ionosphere on azimuth imaging. According to the results of our analysis, we conclude that both the quadratic phase error and the cubic phase error neglected for Low-Earth-Orbit SAR(LEOSAR) will deteriorate the azimuth imaging for MEOSAR and ionospheric effects become more and more serious with the increase of SAR altitude and the improvement of azimuth resolution designed.

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Dr. Liang Li

Dr. Jun Hong